A review of the history of research and control of Rhipicephalus (Boophilus) microplus, babesiosis and anaplasmosis in Uruguay

In Uruguay, control of Rhipicephalus microplus began in 1910. In 1941 the eradication of R. micoplus throughout the country was declared mandatory, although this attempt was unsuccessful. Since 2008 the country was divided into two regions: the south-western region, which is free of ticks; and a region of tick control that includes all departments to the north of the Rio Negro and five departments in the eastern region. In Uruguay, investigations on R. microplus, babesiosis and anaplasmosis started in 1921, and in the 1970s, studies of the epidemiology of R. microplus determined that from 2 to 3.5 generations can be produced annually and that the country is in an area of enzootic instability for babesiosis and anaplasmosis. Knowledge of tick epidemiology and of tick resistance to different acaricides led to the development of efficient methods of control or eradication, including integrated control and generational treatment. Although research results have led to a legal framework regarding R. microplus control, these measures have had variable results. This can be attributed to several factors, such as the discontinuation of the control measures, variable financial resources, changes in the dynamics of livestock movement, failure to adopt available technology for tick control by farmers, climate change, environmental alterations such as forestation and the increasing resistance of ticks to acaricides, which led to the development of multiresistant ticks. This paper reviews the history of R. microplus, babesiosis and anaplasmosis in Uruguay and proposes alternatives for their control.